It is known in connection with open-end spinning rotors to seat the rotor shaft radially in a wedge-like gap formed by pairs of offset support rollers which makes it possible to securely seat a rotor shaft even at very high rotational speeds (rpm). An axial thrust is exerted on the rotor shaft by means of the offset of the shafts of the paired support rollers, which acts in the axial direction toward the outward end of the shaft opposite the rotor in order to securely seat the rotor, even at high rpm. To be able to absorb such axial forces, it is known to seat the outward end of the shaft on a ball, for example, such as described in German Patent Publication DE 25 14 734 C2. Such a bearing, however, is subject to wear.
It has therefore been proposed to simplify the axial seating of the rotor shaft to overcome such wearing problem. It is known from German Patent Publication DE 26 34 070 C3 to axially fix a rotor shaft by means of a magnetic bearing wherein axially magnetized permanent magnets are disposed at the end of the shaft, while maintaining the shaft diameter, and have disk-shaped pole shoes of the same orientation which are fixed in facing relation to each other.
In such a magnetic bearing arrangement, the rotor shaft is not fixed axially as stably as with the arrangement proposed by German Published, Non-Examined Patent Application DE-OS 26 39 763, wherein the magnets are arranged with essentially radially oriented faces containing magnetic poles of the same orientation placed opposite each other at an axial distance, with at least two such faces arranged parallel such that any axial movement of the shaft causes the axial distance between the magnetic faces to be changed in an opposite direction. With the magnetic bearing proposed in this reference, the rotor shaft can only be removed if the bearing is disassembled or is opened by means of a structurally elaborate mechanism.